Rush University researchers find link between diet and depression

Rush University Medical Center researchers have published a study which found that a diet designed to reduce hypertension also showed associated lower rates of depression.

The comprehensive research project observed 964 participants over a six-year period. The subjects were split into three groups based on their ability to follow the Dietary Approaches to Stop Hypertension (DASH) diet. The participants were evaluated in yearly increments to see if the diet improved their mental health and wellbeing. Those who followed the DASH diet most closely were least likely to develop depression than the other groups, the study found.

The DASH diet focuses on restricting sodium intake and increasing consumption of fresh fruits and vegetables, whole grains and low fat-dairy. It was ranked as one of the healthiest diets in a US News ‘Best Diets Overall’ survey of forty diets in January 2018.

Study author and assistant professor of Neurology Laurel Cherian conceded that the observation was associational–meaning that the research could not confirm that healthy eating reduces the risk of depression.

“Depression is common in older adults and more frequent in people with memory problems, vascular risk factors such as high blood pressure or high cholesterol, or people who have had a stroke,” said Cherian.

“There is evidence linking healthy lifestyle changes to lower rates of depression and this study sought to examine the role that diet plays in preventing depression.”

A trial conducted at Deakin University aimed to investigate the link further; examining 67 adults diagnosed with major depressive disorder and divided them into two groups. The first group followed a Mediterranean-style diet of fresh fruit, vegetables, fish, and nuts. The second group was placed in social support programme, a conventional treatment for depression.

“These results were not explained by changes in physical activity or body weight, but were closely related to the extent of dietary change,” said co-author Felice Jacka.

“Those who adhered more closely to the dietary program experienced the greatest benefit to their depression symptoms.”

A large meta-analysis of 24 studies conducted last year showed only mild correlations between healthy diets and lower rates of depression. There was no tangible link found between bad diet and high depression.

The studies bring into the limelight the hypothesis that gut bacteria has a considerable role to play in neurochemistry. A small study previously indicated that probiotics can reduce the symptoms of depression. Gut bacteria has also been linked to PTSD and Alzheimer’s disease.